unplugging of network cable makes jgroups behave weirdly

Hi,
I am using jgroups 2.2.9 for communication in my cluster.
I was checking the behaviour of jgroups to network fluctuation.
for that I manually unplug the network cable and plug it back after some time.
But jgroups keeps sending suspected messages and never bring that into the cluster.

I have two machines in my cluster A(10.200.1.92) & B(10.200.1.74).
I unplug the cable in machine B. and plug it back . but B never joined the cluster.
Please find the attachment for the log files from both the machines.

I am using TCP based communication. I set up my protocol stack using . MPING,MERGE2,FD,VERIFY_SUSPECT,pbcast.NAKACK,pbcast.STABLE,VIEW_SYNC,pbcast.GMS.

The following are the confuguration in both the machines.

configuration setting in Machine-A
notificationbus.properties:
TCP(bind_addr=boca;recv_buf_size=200000;send_buf_size=100000;loopback=true;
start_port=7880):
MPING(timeout=4000;bind_to_all_interfaces=true;mcast_addr=228.8.8.8;mcast_port=7500;
ip_ttl=8;num_initial_members=4;num_ping_requests=1):
MERGE2(max_interval=10000;min_interval=5000):
FD(timeout=2000;max_tries=3):
VERIFY_SUSPECT(timeout=1500;down_thread=false;up_thread=false):
pbcast.NAKACK(max_xmit_size=60000;gc_lag=50;
retransmit_timeout=100,200,300,600,1200,2400,4800):
pbcast.STABLE(stability_delay=1000;desired_avg_gossip=20000;down_thread=false;
up_thread=false;max_bytes=0):
VIEW_SYNC(avg_send_interval=60000;down_thread=false;up_thread=false):
pbcast.GMS(print_local_addr=true;join_timeout=5000;join_retry_timeout=2000;shun=true)

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configuration setting in Machine-B
notificationbus.properties:
TCP(bind_addr=rizal;recv_buf_size=200000;send_buf_size=100000;
loopback=true;start_port=7880):
MPING(timeout=4000;bind_to_all_interfaces=true;mcast_addr=228.8.8.8;
mcast_port=7500;ip_ttl=8;num_initial_members=4;num_ping_requests=1):
MERGE2(max_interval=10000;min_interval=5000):FD(timeout=2000;max_tries=3):
VERIFY_SUSPECT(timeout=1500;down_thread=false;up_thread=false):
pbcast.NAKACK(max_xmit_size=60000;gc_lag=50;
retransmit_timeout=100,200,300,600,1200,2400,4800):
pbcast.STABLE(stability_delay=1000;desired_avg_gossip=20000;down_thread=false;
up_thread=false;max_bytes=0):
VIEW_SYNC(avg_send_interval=60000;down_thread=false;up_thread=false):
pbcast.GMS(print_local_addr=true;join_timeout=5000;join_retry_timeout=2000;shun=true)
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